Duckasaurus Background

The plane that could

The Duckasaurus was born out of tragedy. Originally during the 2021-2022 season, we had an pre-purchased aircraft called the Swallow that was our planned competition plane while the previously named Carbon Copy was being created. During one of our first test flights, the Swallow had a catastrophic crash. There was a really good video of the crash however that video has been lost to ages. Hopefully we can find it and upload it here for trauma. This was about 10 weeks before the competition and we had to decide to whether drop of out the competition or remake the plane. We had decided to reamke the plane, creating a simplified, yet sturdy design with a quick manufacturing turnaround, the two main goals we had considered. The result was that we had completed the Duckasaurus and managed to finish 5th in the 2022 SUAS AUVSI competition in Maryland!

Duckasaurus Design

The Duckasaurus' fuselage, wings, and tail were optimized aerodynamically while keeping the manufacturing relatively quick and simple. In general, all parts were made of XPS foam and cut using a hand hot wire cutter with laser cut wooden templates.

Starting with the wings we had chosen a NACA 2412 airfoil, meaning maximum camber is 2% of the chord length, with the max 40% from the leading edge of the chord, with a maximum thickness of 12% of the chord. The wings also were not swept, there was no taper and no dihedral, further simplifying the design. A symmetric airfoil could work for our purposes, however with camber we could produce more lift at the same angle of attack. The vertical and horizontal stabilizers were similar in design, however the vertical stabilizer had a small taper centered at the quarter chord, or the aerodynamic center, and was slightly swept. The wing span is 10 ft broke up into three sections for packaging purposes. The midsection of the wing is permanently attached to the fuselage, and the two other ends are detachable with tabs that have holes in them for the fasteners to go through to hold the wings together. The nose area has a top that is also removable, it is attached by dual lock so that we can access the front electronics. The midsection wing has a rectangle cut out of it to reach the midsection electronics.

The fuselage was a bit more complicated. The idea was to create a rounded nose with a nose tip that is wide enough to hold the motor. A longer, slender body with rounded corners and a hollow interior with removable tops for inside acces was required. We went with a linear nose which is not as smooth as a rounded nose, but is less complicated to manufacture. The total length of the fuselage is about 1.1 m.

Duckasaurus Manufacturing

Manufacturing materials were made up of plywood, xps foam, fiberglass, and a epoxy. The first step was the general 3D modeling of all of the wooden templates for the wings and tail. After the model was complete, it was sent to the laser cutter in the EnVision center. By sent, I mean you put the file into a USB drive and walk to the EnVision center and plug it in. Once we had the wood cut out, we hot glued it onto the stacks of foam corresponding to the thickness required and basically followed the template to get the positives of the cut. Once we had the positives, we could then do a wet-composite layup on the wings will layers of fiberglass. Other parts like the motor and landing gear mounts were 3 laser cut pieces of wood with embedded nuts in the middle piece. These pieces were then bonded together with epoxy mixed with microballoons. The control surfaces were cut with a knife with the hinges being prebought and placed in small slits between the control surface itself and the wing. There is a diagonal cut that was made in each control surface so that when it deflects downwards it does not hit the wing prematurely.

Duckasaurus test flight, 2022